Internal combustion engines are employed on various devices, including mobile platforms, to generate torque for traction and other applications. An internal combustion engine can be an element of a powertrain architecture operative to transmit torque through a transmission device to a vehicle driveline. The powertrain architecture can further include one or more electrical machines working in concert with the engine. During ongoing operation of the mobile platform employing the internal combustion engine, it may be advantageous to discontinue firing one or more of the cylinders, including stopping engine operation and engine rotation completely. It may be further advantageous to subsequently have knowledge of pressure within the cylinder, to effectively spin, fire, and restart the engine during ongoing operation, to control and manage engine torque vibration, reduce noise, and improve overall operational control of the powertrain.
Prior art systems use models developed off-line to determine cylinder pressure. Such systems are advantageous in that they minimize need for real-time computations. However, such systems have relatively poor accuracy, due to variations introduced by real-time variations in factors including atmospheric pressure, engine speed, initial engine crank angle, engine wear characteristics, and others. Therefore, there is a need to accurately determine engine cylinder pressure in real-time during ongoing operation of the engine.